In recent years, a transparent organic polymer material has been used as a transparent material in place of an inorganic glass, and has been employed, for example, in optical components or the like. The optical component is required to have generally required properties such as transparency, thermal properties, mechanical properties as well as a high refractive index.
One of the conventional techniques concerning such a resin is described in Patent Document 1. In this Document, a thietane compound containing a metal is described. In addition, an optical resin having a high refractive index exceeding 1.7 is described.
Patent Document 2 describes a polymerizable composition which includes a compound containing Sn as a common ring-member atom on two hetero rings and a polythiol.    [Patent Document 1] Pamphlet of International Publication No. 2005-095490    [Patent Document 2] Japanese Unexamined Patent Application Publication No. 2006-143782    [Patent Document 3] GB Patent Publication No. 712828    [Patent Document 4] Japanese Unexamined Patent Application Publication No. 2003-327583    [Patent Document 5] Japanese Unexamined Patent Application Publication No. 2007-269648    [Patent Document 6] Japanese Unexamined Patent Application Publication No. 2007-269649    [Patent Document 7] Japanese Unexamined Patent Application Publication No. 2007-271744    [Non-Patent Document 1] Journal of the Chemical Society (1965), 7098-7102